000 AXNT20 KNHC 131709 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU JUL 13 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1700 UTC. ...TROPICAL WAVES... A WELL-DEFINED TROPICAL WAVE IS ALONG 25W SOUTH OF 16N MOVING WEST 15-20 KT. LOW-MID LEVEL CYCLONIC TURNING IS CLEARLY EVIDENT ON VISIBLE SATELLITE IMAGERY. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 180 NM EITHER SIDE OF THE WAVE AXIS. A TROPICAL WAVE IS ALONG 48W SOUTH OF 14N MOVING WEST NEAR 15 KT. THIS WAVE IS NOT VERY WELL DEFINED AT THIS TIME. LITTLE SHOWER ACTIVITY IS DIRECTLY ASSOCIATED WITH THIS FEATURE. A TROPICAL WAVE HAS MOVED INTO THE EASTERN CARIBBEAN ALONG 64W SOUTH OF 22N MOVING WEST NEAR 15 KT. THIS WAVE REMAINS EASY TO LOCATE. THE VORTICITY MAXIMUM OR ILL-DEFINED SFC LOW THAT WAS ALONG THE WAVE YESTERDAY HAS DISSIPATED OVERNIGHT BUT A NEW SMALL BURST OF CONVECTION HAS DEVELOPED FROM 12N-14N BETWEEN 63W-65W TODAY. DESPITE THE FAIR WAVE SIGNATURE...FURTHER DEVELOPMENT IS NOT EXPECTED AT THIS TIME DUE TO UNFAVORABLE UPPER LEVEL WINDS. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 300 NM BEHIND THE WAVE AXIS. AN EARLIER QUIKSCAT PASS SHOWS AN INCREASE IN THE WINDS BEHIND THE AXIS ESPECIALLY IN THE CONVECTION. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 84W SOUTH OF 17N MOVING WEST 10 TO 15 KT. LITTLE SIGNATURE IS EVIDENT ON VISIBLE SATELLITE IMAGERY. HOWEVER...THIS WAVE MAY BE ENHANCING CLUSTERS OF MODERATE TO STRONG CONVECTION IN THE ITCZ. ...ITCZ... BESIDES FOR THE CONVECTION ASSOCIATED WITH THE EASTERN ATLANTIC TROPICAL WAVE...THE ITCZ IS RELATIVELY QUIET WITH ONLY SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 240 NM EITHER SIDE OF THE AXIS. ...DISCUSSION... GULF OF MEXICO... A SURFACE TROUGH...THAT WAS IN THE W BAHAMAS AND OVER SOUTH FLORIDA YESTERDAY HAS TRACKED WESTWARD INTO THE EASTERN GULF OF MEXICO. AS OF 1500 UTC...THE BOUNDARY LIES ALONG 29N86W 26N83W 23N82W. SCATTERED SHOWERS AND TSTMS ARE WITHIN 90 NM EITHER SIDE OF THE TROUGH AXIS N OF 26N. DOPPLER RADAR INDICATES A POSSIBLE SMALL SURFACE LOW DEVELOPING ALONG THE TROUGH NORTHWEST OF KEY WEST WHERE THERE IS A LARGER AREA OF RAINFALL SOUTH OF 26N...NAMELY WITHIN 180 NM EITHER SIDE OF THE TROUGH AXIS. THE OTHER FEATURE IN THE GULF...IS A LARGE UPPER LEVEL LOW WHICH IS NOW CENTERED NEAR 23N94W. UPPER LEVEL DIFFLUENCE IS GENERATING ISOLATED/SCATTERED SHOWERS ESPECIALLY ON THE MOIST EAST SIDE OF THE UPPER LEVEL CIRCULATION FROM THE YUCATAN PENINSULA TO THE CENTRAL AND WESTERN GULF. BOTH THE UPPER LEVEL LOW AND SFC TROUGH WILL CONTINUE TO TRACK WESTWARD ACROSS THE GULF OF MEXICO OVER THE NEXT COUPLE OF DAYS. MOISTURE ASSOCIATED WITH THE SFC TROUGH WILL MOVE INTO THE CENTRAL GULF OF MEXICO TOMORROW ALLOWING THE EASTERN GULF AND FLORIDA TO CLEAR OUT. THE CARIBBEAN SEA... AN UPPER LEVEL TROUGH/RIDGE PATTERN REMAINS IN PLACE ACROSS THE CARIBBEAN SEA. THE UPPER TROUGH EXTENDS FROM THE BAHAMAS TO THE SW CARIBBEAN NEAR 12N80W. DRY/STABLE AIR IS ASSOCIATED WITH THE TROUGH...SINKING SOUTHWESTWARD. WEAK UPPER RIDGING LIES TO THE EAST OF THE TROUGH WITH THE UPPER AXIS ALONG 68W-70W. THE MAIN WEATHER PRODUCING FEATURE IN THE AREA IS A TROPICAL WAVE IN THE EASTERN CARIBBEAN. SCATTERED SHOWERS AND TSTMS ARE MOSTLY BEHIND THE WAVE AXIS ACROSS THE LESSER ANTILLES. A SMALL BURST OF MODERATE CONVECTION DEVELOPED EARLIER TODAY IS CURRENTLY FROM 12N-14N BETWEEN 63W-65W. WHILE DEVELOPMENT DOES NOT APPEAR LIKELY...THIS WAVE WILL CARRY MOISTURE TO PUERTO RICO AND HISPANIOLA TONIGHT AND TOMORROW. TRADE WINDS ARE GENERALLY NEAR 20 KT ACROSS THE AREA WITH A SLIGHT INCREASE IN THE WINDS BEHIND THE WAVE AXIS... ESPECIALLY IN AREAS OF CONVECTION. NUMEROUS MODERATE TO STRONG CONVECTION...ASSOCIATED WITH THE ITCZ...HAS MOVED OFF THE COAST OF COLOMBIA AND IS NOW IN THE EAST PACIFIC BASIN. THE ATLANTIC OCEAN... A BROAD BERMUDA-AZORES RIDGE LIES ACROSS THE ENTIRE ATLANTIC BASIN WITH A COUPLE OF HIGH PRES CENTERS NORTH OF THE DISCUSSION AREA. THIS HIGH PRES RIDGE IS SUPPLYING PLENTY OF FAIR TRANQUIL WEATHER ACROSS A LARGE PORTION OF THE ATLANTIC. THE ONLY AREAS OF UNSETTLED WEATHER IS ASSOCIATED WITH THE TROPICAL WAVES WHICH ARE DISCUSSED IN THAT SECTION. IN THE UPPER LEVELS...RIDGING IS MOSTLY THE THEME WITH A BROAD UPPER HIGH CENTERED OFF THE CAROLINA COASTLINE WITH RIDGING EXTENDING TO 50W. A NARROWER AMPLIFIED UPPER HIGH IN THE EAST ATLANTIC IS CENTERED NEAR 26N21W WITH RIDGING EXTENDING WESTWARD TO 30W. IN BETWEEN THE BROAD UPPER RIDGING A NARROW WEAK UPPER TROUGH LIES NORTH OF 27N. MODERATE TO STRONG SUBSIDENCE COVERS A LARGE PORTION OF THE BASIN. LITTLE CHANGE IN THE OVERALL PATTERN IS EXPECTED OVER THE NEXT COUPLE OF DAYS. $$ CANGIALOSI